Delhi breathes 'very poor' air; dense fog, light rain likely over next two days

New Delhi, Dec 30 (PTI) The national capital's air quality improved marginally to the 'very poor' category on Tuesday, even as dense fog reduced visibility in parts of the city.

The India Meteorological Department (IMD) has predicted that the dense fog is likely to persist on Wednesday.

Delhi recorded a 24-hour average Air Quality Index (AQI) of 388, down from 401 on Monday, according to Central Pollution Control Board (CPCB) data.

While 17 air quality monitoring stations in Delhi recorded pollution levels in the 'very poor' category, another 17 logged 'severe' readings.

Anand Vihar recorded the worst AQI at 460, according to the CPCB's Sameer app.

An AQI between 0 and 50 is considered 'good', 51 to 100 'satisfactory', 101 to 200 'moderate', 201 to 300 'poor', 301 to 400 'very poor', and 401 to 500 'severe'.

The Air Quality Early Warning System said the AQI is likely to be in the 'severe' category on December 31 and January 1, before returning to the 'very poor' category on January 2.

For the subsequent six days, the air quality is expected to remain in the 'very poor' category.

Officials attributed the poor outlook to an unfavourable ventilation index of less than 6,000 sq m per second and average wind speeds of less than 10 kmph, which are not conducive for the dispersion of pollutants.

According to the Decision Support System (DSS) for Air Quality Management, Delhi transport was the biggest contributor to air pollution on Tuesday at 15.3 per cent, followed by industries in the city and its peripheral areas at 7.6 per cent, residential sources at 3.7 per cent, construction activities at 2 per cent and waste burning at 1.3 per cent.

Among NCR districts, Jhajjar was the biggest contributor at 18.2 per cent, followed by Rohtak at 4.7 per cent, Bhiwani at 4.4 per cent, Gurugram at 1.8 per cent and Sonipat at 1.4 per cent.

Delhi recorded a maximum temperature of 21.5 degrees Celsius, 1.1 notches above normal, and a minimum of 9.4 degrees Celsius, 2.6 notches above normal.

Low visibility conditions prevailed during the morning hours due to dense fog.

The visibility at Safdarjung was recorded at around 100 metres at 7.30 am and it improved to around 200 metres by 8.30 am. At Palam, moderate fog was observed, with visibility around 300 metres at 8.30 am.

The IMD has forecast dense fog on Wednesday. The minimum temperature is expected to settle at 8 degrees Celsius and the maximum at 23 degrees Celsius.

It has forecast generally cloudy skies with light rain on New Year's Day. PTI SGV DIV DIV